Dental impression-tray.



R. M. KERR. i DENTAL IMPRESSION TRAY. APPLICATION FILED MAY 20, 1914.

1,127,635. Patent etl Feb. 9, 1915.

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ROBERT M. KERR, 015 DETROIT, MICHIGAN, ASSIGNOR T0 DETROIT DENTAL MANUFAC- TUBING COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

DENTAL IMPRESSION-TRAY.

Specification of Letters Patent.

Patented Feb. 9, 1915.

Application filed May 20, 1914. Serial No. 839,680.

To all whom it may concern Be it known that I, ROBERT M. KERR, a citizen of the United States of America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Dental Impression-Trays, of which the following is aspecification, reference being had therein to the accompanying drawings.

The invention relates to dental impression trays of that type in which the handle is removable to permit the patient to close the mouth.

It is the object of the invention to obtain a construction which is inexpensive to manufacture and which permits of forming both the tray and the handle of stampings with integral securing means.

In the drawings: Figure 1 and Fig. 2 are perspective views respectively of the.tray and handle in reverse position and detached from each other; Fig. 3 is a bottom plan view showing the handle in engagement with the tray; Fig. 4 is a longitudinal section therethrough; and Fig. 5 is a cross section.

A is the tray which is formed of a stamping of suitable material, such for instance as aluminum.

B are loops struck out from the bottom of the tray by the forming operation and which form securing sockets for the prongs of the handle C. This handle is preferably formed with the divergent prongs D and D for respectively engaging the loops B and B upon opposite sides of the tray, and a central short prong D for engaging the loop B All of these prongs are preferably formed in the same plane, and as the loops are also in a common plane the handle may be readily engaged or disengaged by a telescopic movement.

In use, the struck-out loops do not interferewith the placing of the impression material in the tray, nor does this material interfere with the adjustment or detachment of the handle. Consequently the handle may be used for placing the tray in the mouth and removing it from the same, and may be detached from the tray while it remains in the mouth. The recesses formed in the bottom of the tray by the struck out loops perform another function, viz., in the anchoring of the plastic material in the tray. It has been found in practice that it is difficult to cause certain plastic compounds to adhere to the smooth surface of the tray, but where there are depressions or perforations an interlock is formed which increases the adhesion.

To secure the handle from accidental displacement, the engagement between the prongs and the struck-out loops is preferably such as to produce a resilient tension. This will introduce the desired degree of friction to hold the handle in place without interfering with its removal when desired.

What I claim as my invention is A dental tray formed of a stamping having a plurality of loops struck downward from the bottom portion thereof, and arranged in a common plane, and a handle formed from a flat sheet of metal having a plurality of prongs registerable with the respective loops and telescopically engageable therewith, all of said prongs being disengageable from the respective loops by movement in a single direction.

In testimony whereof I afiix my signature in presence of two witnesses.

ROBERT M. KERR.

Witnesses:

JAMES P. BARRY, HENRIETTA E. BOWMAN.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

